A linear voltage regulator, chip and electronic device without external capacitor

Abstract

The present application provides a linear voltage regulator, chip and electronic device without external capacitors. The linear voltage regulator includes: a first regulating circuit, a first constant-pass circuit, a second passable circuit, a pull-down voltage circuit, a power output circuit and a first current source; the first end of the first regulating circuit is connected to the output end, and the second end is respectively connected to the first end of the first constant-pass circuit and the first end of the second passable circuit; the second end of the first constant-pass circuit is grounded, the second end of the second passable circuit is connected to the first end of the pull-down voltage circuit, and the second end of the pull-down voltage circuit is connected to the control end of the power output circuit; the first regulating circuit turns on the second passable circuit when the first current source indicates that the output voltage has suddenly increased; the pull-down voltage circuit works after the second passable circuit is turned on; after the pull-down voltage circuit works, the working state of the power output circuit changes and the output voltage decreases. When the linear voltage regulator outputs a voltage, the stability of the output voltage of the output end can be made higher.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a linear voltage regulator, a chip and an electronic device without external capacitors. Background Art

[0002] Implementing a linear regulator without external capacitors in an electronic device structure can save costs. For example, implementing a linear regulator without external capacitors in a chip can eliminate an output pad, a package metal bond wire, and an external capacitor.

[0003] However, linear regulators without external capacitors have poor transient response capabilities. For example, when the load current in a linear regulator without external capacitors changes significantly and rapidly, the output voltage of the corresponding linear regulator without external capacitors will fluctuate significantly. Large fluctuations in the output voltage of a linear regulator without external capacitors can easily cause lower-level logic circuits to output erroneous logic signals. Furthermore, when the output voltage of a linear regulator without external capacitors exceeds the safe power supply range, it can easily damage the device. Both the device and the lower-level logic circuit are connected to a linear regulator without external capacitors.

[0004] Therefore, the application scenarios of linear regulators without external capacitors are relatively limited, and can only be used in scenarios where the load is relatively stable or changes slowly and with a small amplitude. Summary of the Invention

[0005] The present application provides a linear regulator, chip and electronic device without external capacitors to solve the problem that the linear regulator without external capacitors can only be used in scenarios where the load is relatively stable or changes slowly and with a small amplitude.

[0006] In a first aspect, the present application provides a linear voltage regulator without an external capacitor, the linear voltage regulator comprising: an amplifier, a first regulating circuit, a first constant-on circuit, a second passable circuit, a voltage pull-down circuit, a power output circuit, a voltage feedback circuit, and a first current source;

[0007] The positive input terminal of the amplifier is used to receive a reference voltage, the negative input terminal of the amplifier is used to receive a feedback voltage, the output terminal of the amplifier is electrically connected to the control terminal of the power output circuit, the first terminal of the power output circuit is used to receive a power supply voltage, the second terminal of the power output circuit is electrically connected to the output terminal of the linear regulator and the first terminal of the voltage feedback circuit respectively, the output terminal of the linear regulator is used to receive an output voltage, the second terminal of the voltage feedback circuit is grounded, the third terminal of the voltage feedback circuit is used to output the feedback voltage, the first terminal of the first current source is also electrically connected to the output terminal of the linear regulator, and the second terminal of the first current source is grounded;

[0008] The first end of the first regulating circuit is also electrically connected to the output end of the linear regulator, the second end of the first regulating circuit is electrically connected to the first end of the first constant-on circuit and the first end of the second passable circuit respectively, the second end of the first constant-on circuit is grounded, the second end of the second passable circuit is electrically connected to the first end of the pull-down voltage circuit, and the second end of the pull-down voltage circuit is also electrically connected to the control end of the power output circuit;

[0009] a first regulating circuit, configured to ground the first constant-on circuit and cut off the second passable circuit when the first current source does not indicate a sudden increase in the output voltage;

[0010] The voltage-lowering circuit is configured to stop working after the second passable circuit is cut off; wherein, when the voltage-lowering circuit stops working, the working state of the power output circuit remains unchanged, so that the output voltage is output;

[0011] The first regulating circuit is further configured to ground the first constant-on circuit and turn on the second passable circuit when the first current source indicates that the output voltage suddenly increases;

[0012] The voltage-lowering circuit is further configured to operate after the second passable circuit is turned on; wherein, after the voltage-lowering circuit operates, the operating state of the power output circuit changes to reduce the output voltage.

[0013] When the output voltage of the linear regulator without off-chip capacitors provided by the first aspect of the present application suddenly increases, a first current is generated in the first regulation circuit. The first current can cause a second passable circuit connected to the first regulation circuit to conduct. The first current enters the pull-down voltage circuit through the second passable circuit, increasing the current in the pull-down voltage circuit. The increased current in the pull-down voltage circuit can lower the voltage at the control terminal of the power output circuit. The output voltage of the power output circuit is stable. Furthermore, the stable output voltage of the power output circuit can stabilize the output voltage of the output terminal of the linear regulator.

[0014] When the linear voltage regulator without external capacitors according to the present application outputs a voltage, the first regulating circuit, the first constant-on circuit, the second passable circuit, and the voltage-lowering circuit in the linear voltage regulator can lower the voltage at the control terminal of the power output circuit in the linear voltage regulator. This makes the output voltage stability of the output terminal of the linear voltage regulator higher. Furthermore, it can effectively avoid the problem that when the output voltage of the linear voltage regulator without external capacitors changes significantly, the lower-level logic circuit outputs an erroneous logic signal, and when the output voltage of the linear voltage regulator without external capacitors exceeds the safe power supply range, the device is damaged. Furthermore, the linear voltage regulator without external capacitors can be widely used in various technical fields.

[0015] In one possible design, the first regulating circuit includes: a first transistor, a second transistor, a second current source, a first capacitor, and a first resistor;

[0016] A first end of the first transistor is electrically connected to the output end of the linear regulator, a second end of the first transistor is electrically connected to the first end of the first capacitor, and a third end of the first transistor is electrically connected to the first end of the first constant-on circuit and the first end of the second passable circuit respectively;

[0017] A first terminal of the second transistor is electrically connected to the output terminal of the linear regulator, a second terminal of the second transistor is electrically connected to the first terminal of the first resistor, and a third terminal of the second transistor is electrically connected to the first terminal of the second current source; a second terminal of the second current source is grounded; and a second terminal of the first capacitor is grounded.

[0018] The second end of the first resistor is electrically connected to the first end of the first capacitor.

[0019] In one possible design, the linear regulator further includes: a second regulating circuit, wherein a first end of the second regulating circuit is also electrically connected to the output end of the linear regulator, and a second end of the second regulating circuit is electrically connected to the first end of the pull-down voltage circuit;

[0020] a second regulating circuit, configured to ground the first constant-on circuit within a first duration when the first current source indicates that the output voltage has suddenly increased;

[0021] The first regulating circuit is specifically configured to ground the first constant-on circuit and turn on the second passable circuit after a second time period when the first current source indicates that the output voltage suddenly increases.

[0022] In one possible design, the second regulating circuit includes: a second capacitor;

[0023] A first end of the second capacitor is electrically connected to the output end of the linear regulator, and a second end of the second capacitor is electrically connected to the first end of the pull-down voltage circuit.

[0024] In one possible design, the first constant-on circuit includes: a third current source; a first end of the third current source is electrically connected to the second end of the first regulating circuit, and a second end of the third current source is grounded.

[0025] In one possible design, the second passable circuit includes: a diode, the anode of the diode is electrically connected to the second end of the first regulating circuit, and the cathode of the diode is electrically connected to the first end of the pull-down voltage circuit.

[0026] In one possible design, the pull-down voltage circuit includes: a third transistor, a fourth transistor, and a fourth current source;

[0027] a first terminal of the third transistor is grounded, a second terminal of the third transistor is electrically connected to the second terminal of the fourth transistor, and a third terminal of the third transistor is electrically connected to the cathode of the diode;

[0028] A first terminal of the fourth transistor is grounded, and a third terminal of the fourth transistor is electrically connected to a control terminal of the power output circuit;

[0029] A first end of the fourth current source is electrically connected between the second end of the third transistor and the second end of the fourth transistor, and a second end of the fourth current source is used to access a power supply voltage.

[0030] In one possible design, the power output circuit includes: a fifth transistor;

[0031] a first end of the fifth transistor being used to access a power supply voltage, a second end of the fifth transistor being electrically connected to an output end of the amplifier, and a third end of the fifth transistor being electrically connected to an output end of the linear regulator and a first end of the voltage feedback circuit, respectively;

[0032] The voltage feedback circuit includes: a second resistor and a third resistor;

[0033] A first end of the second resistor is electrically connected to the output end of the linear regulator, and a second end of the second resistor is electrically connected to a first end of the third resistor;

[0034] A second end of the third resistor is grounded;

[0035] The third terminal of the voltage feedback circuit is located between the second terminal of the second resistor and the first terminal of the third resistor.

[0036] In a second aspect, the present application provides a chip comprising any of the linear regulators described above.

[0037] In a third aspect, the present application provides an electronic device comprising any of the linear regulators described above.

[0038] The beneficial effects provided in the above-mentioned second aspect and the various possible designs of the above-mentioned second aspect can be referred to the beneficial effects brought about by the above-mentioned first aspect and the various possible implementation methods of the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic structural diagram of a linear voltage regulator without external capacitors provided in the first aspect of the present application;

[0040] Figure 2 A circuit diagram of a linear voltage regulator without external capacitors provided in the first aspect of the present application;

[0041] Figure 31 is a comparison diagram of the output voltage change curves corresponding to the linear regulator of the present application and the first linear regulator when the current of the first current source changes. DETAILED DESCRIPTION

[0042] In this application, "at least one" means one or more, and "more" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a alone, b alone, or c alone can mean: a alone, b alone, c alone, a and b combined, a and c combined, b and c combined, or a, b, and c combined, where a, b, and c can be single or plural. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0043] The directions or positional relationships indicated by terms such as "center", "longitudinal", "lateral", "up", "down", "left", "right", "front", and "back" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the present application.

[0044] The terms "connected" and "connect" should be interpreted broadly. For example, "connected" or "connected" in a circuit structure can refer not only to a physical connection, but also to an electrical connection or a signal connection. For example, it can be a direct connection, i.e., a physical connection, or an indirect connection through at least one intermediate component, as long as the circuit is interconnected. It can also refer to internal connectivity between two components. Signal connection can refer not only to signal connection through circuits but also to signal connection through media, such as radio waves. Those skilled in the art will understand the specific meanings of the above terms in this application on a case-by-case basis.

[0045] refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a linear voltage regulator without external capacitors provided in the first aspect of the present application. The first aspect of the present application provides a linear voltage regulator without external capacitors, the linear voltage regulator comprising: an amplifier 1, a first regulation circuit, a first constant-on circuit, a second passable circuit, a voltage pull-down circuit, a power output circuit, a voltage feedback circuit, and a first current source I1.

[0046] The positive input terminal of the amplifier 1 is used to receive a reference voltage, the negative input terminal of the amplifier 1 is used to receive a feedback voltage, the output terminal of the amplifier 1 is electrically connected to the control terminal of the power output circuit, the first terminal of the power output circuit is used to receive a power supply voltage, the second terminal of the power output circuit is electrically connected to the output terminal A2 of the linear regulator and the first terminal of the voltage feedback circuit respectively, the output terminal A2 of the linear regulator is used to receive the output voltage, the second terminal of the voltage feedback circuit is grounded, the third terminal A3 of the voltage feedback circuit is used to output the feedback voltage, the first terminal of the first current source I1 is also electrically connected to the output terminal A2 of the linear regulator, and the second terminal of the first current source I1 is grounded.

[0047] The first end of the first regulation circuit is also electrically connected to the output end A2 of the linear regulator, and the second end of the first regulation circuit is respectively electrically connected to the first end of the first constant-pass circuit and the first end of the second passable circuit. The second end of the first constant-pass circuit is grounded, and the second end of the second passable circuit is electrically connected to the first end of the pull-down voltage circuit. The second end of the pull-down voltage circuit is also electrically connected to the control end of the power output circuit.

[0048] The first regulating circuit is configured to ground the first constant-on circuit and cut off the second passable circuit when the first current source I1 does not indicate that the output voltage suddenly increases.

[0049] The voltage-lowering circuit is used to stop working after the second passable circuit is cut off; wherein, when the voltage-lowering circuit stops working, the working state of the power output circuit remains unchanged to output the output voltage.

[0050] The first regulating circuit is further configured to ground the first constant-on circuit and turn on the second passable circuit when the first current source I1 indicates that the output voltage suddenly increases.

[0051] The voltage-lowering circuit is further configured to operate after the second passable circuit is turned on; wherein, after the voltage-lowering circuit operates, the operating state of the power output circuit changes to reduce the output voltage.

[0052] refer to Figure 1 When the linear voltage regulator without off-chip capacitors provided by the first aspect of the present application outputs a voltage, when the output voltage connected to the output terminal A2 of the linear voltage regulator suddenly increases, a first current is generated in the first regulation circuit. The first current can make the second passable circuit and the first constant-pass circuit connected to the first regulation circuit conductive. After the first current is shunted, it enters the pull-down voltage circuit through the second passable circuit, and the current in the pull-down voltage circuit increases. The increase in the current in the pull-down voltage circuit can pull down the voltage of the control terminal of the power output circuit. The output voltage of the power output circuit is stable. Furthermore, the stable output voltage of the power output circuit can stabilize the output voltage of the output terminal A2 of the linear voltage regulator.

[0053] refer to Figure 1 When the linear regulator without external capacitors of the present application outputs a voltage, the first regulating circuit, the first constant-on circuit, the second enable circuit, and the voltage-lowering circuit in the linear regulator can lower the voltage at the control terminal of the power output circuit. This effectively reduces the amplitude of any sudden increase in the output voltage at the output terminal A2 of the linear regulator. This ensures that the output voltage at the output terminal A2 of the linear regulator is more stable, preventing significant overshoot spikes.

[0054] Furthermore, the output voltage of the linear regulator of the present application can effectively prevent the problem of a downstream logic circuit outputting erroneous logic signals when the output voltage of a linear regulator without external capacitors fluctuates significantly, and the problem of damage to components in the downstream circuit when the output voltage of the linear regulator without external capacitors exceeds the safe power supply range, thereby ensuring the functionality and performance of the downstream circuit. Furthermore, the linear regulator without external capacitors of the present application can be widely used in various technical fields.

[0055] The devices and circuit structures in the linear regulator without off-chip capacitors of the present application include but are not limited to: an amplifier 1, a first regulation circuit, a first constant-on circuit, a second passable circuit, a pull-down voltage circuit, a power output circuit, a voltage feedback circuit, and a first current source I1. Devices and circuit structures may also be added based on specific needs.

[0056] Amplifier 1 in the capacitor-free linear regulator of the present application includes a positive input, a negative input, and an output. Amplifier 1 may be an error amplifier 1. The positive input of amplifier 1 is used to input a reference voltage. The reference voltage is a preset constant voltage that serves as a reference voltage for various voltages input to amplifier 1.

[0057] The inverting input terminal of amplifier 1 is used to input a feedback voltage. The inverting input terminal of amplifier 1 can also be electrically connected to the third terminal A3 of the voltage feedback circuit to input the feedback voltage. The output terminal of amplifier 1 is electrically connected to the control terminal of the power output circuit to supply power to the control terminal of the power output circuit.

[0058] The amplifier 1 may be any amplifier 1 suitable for a linear regulator without an off-chip capacitor, and the model of the amplifier 1 may be determined based on specific requirements.

[0059] The power output circuit in the linear regulator without off-chip capacitors of the present application includes: a control end, a first end, and a second end. The first end and the control end of the power output circuit are both input ends for inputting voltage. The second end of the power output circuit is an output end for outputting voltage. The first end of the power output circuit is electrically connected to the input end A1 of the linear regulator. The input end A1 of the linear regulator is used to be electrically connected to a power supply to access the power supply voltage. The control end of the power output circuit is electrically connected to the output end of amplifier 1 to access the voltage at the output end of amplifier 1. The second end of the power output circuit is used to be electrically connected to the output end A2 of the linear regulator to output voltage.

[0060] In addition, the second end of the power output circuit is also electrically connected to the first end of the voltage feedback circuit, so as to feed back the output voltage of the second end of the power output circuit to the amplifier 1 .

[0061] The first regulating circuit has a first end and a second end, wherein the first end of the first regulating circuit is an input end and the second end of the first regulating circuit is an output end.

[0062] When the output voltage at output terminal A2 of the linear regulator does not suddenly increase, a second current is generated in the first regulation circuit. At this point, the second current flows into the first constant-on circuit. The magnitude of the second current is less than or equal to the maximum current allowed to flow through the first constant-on circuit.

[0063] When the output voltage at output terminal A2 of the linear regulator suddenly increases, the first regulation circuit generates a first current based on the suddenly increased output voltage. The magnitude of the first current is greater than the magnitude of the second current, and the magnitude of the first current is greater than the maximum current allowed to pass through the first constant-pass circuit. The first current flows through the second terminal of the first regulation circuit and then branches into the first constant-pass circuit and the second passable circuit.

[0064] In addition, the first regulating circuit is in a constant on state, so that when the voltage outputted by the output terminal A2 of the linear regulator suddenly increases, the first regulating circuit can respond quickly.

[0065] The first constant-on circuit in the linear regulator of the present application is in a constant-on state, and the maximum current allowed to pass through the first constant-on circuit can be determined based on specific requirements.

[0066] The first end of the second permeable circuit is an input end, and the second end is an output end. The second permeable circuit can be selectively turned on or off based on the magnitude of the current flowing out of the first regulating circuit. When the current generated by the first regulating circuit is greater than the maximum current allowed to pass through the first constant-pass circuit, the second permeable circuit is turned on. When the current generated by the first regulating circuit is less than or equal to the maximum current allowed to pass through the first constant-pass circuit, the second permeable circuit is in a cutoff state.

[0067] In addition, the second passable circuit is a unidirectional current transmission circuit to prevent the current in the pull-down voltage circuit from flowing into the first regulating circuit through the second passable circuit.

[0068] The voltage-lowering circuit in the linear regulator of the present application is in a constant on state. When the second passable circuit is on, the current in the voltage-lowering circuit is greater than the current in the voltage-lowering circuit when the second passable circuit is off. Furthermore, at this time, the current in the voltage-lowering circuit is greater than the current output by the output terminal of amplifier 1, and the voltage-lowering circuit lowers the voltage at the control terminal of the power output circuit.

[0069] When the voltage reduction circuit stops operating, the components in the voltage reduction circuit are in an on state. When the voltage reduction circuit stops operating, the current in the voltage reduction circuit is low and is less than the current output by the output terminal of amplifier 1. At this time, the voltage reduction circuit does not reduce the voltage at the control terminal of the power output circuit.

[0070] When the voltage reduction circuit is operating, the components in the circuit are in the on state. At this time, the current in the circuit is large and greater than the current output by the output terminal of amplifier 1. The voltage reduction circuit reduces the voltage at the control terminal of the power output circuit.

[0071] Furthermore, when the linear regulator of the present application outputs a voltage, the power output circuit is constantly in a saturated state. The saturated state of the power output circuit includes a stable voltage output state and a voltage mutation state. When the power output circuit is in the stable voltage output state, the input voltage between the control terminal of the power output circuit and the first terminal of the power output circuit remains unchanged. The output voltage of the second terminal of the power output circuit remains stable. When the power output circuit is in the voltage mutation state, the input voltage of the first terminal of the power output circuit remains unchanged, while the output voltage of the second terminal of the power output circuit changes suddenly, and the input voltage of the first terminal of the power output circuit gradually increases as the output voltage of the second terminal of the power output circuit increases.

[0072] refer to Figure 1 When the load current of the first current source I1 does not suddenly change from a heavy load current to a light load current, the first current source I1 does not indicate a sudden increase in the output voltage at the output terminal A2 of the linear regulator. At this point, the input voltage at the first terminal of the first regulation circuit is stable, and a second current is generated in the first regulation circuit. The first constant-on circuit is grounded, the second enable circuit is cut off, the voltage-lowering circuit is deactivated, and the power output circuit maintains a stable voltage output state.

[0073] refer to Figure 1When the load current of the first current source I1 suddenly changes from a heavy load current to a light load current, the output voltage at the output terminal A2 of the linear regulator, which is directed by the first current source I1, suddenly increases. At this time, the input voltage at the first terminal of the first regulation circuit suddenly increases, generating a first current in the first regulation circuit. The first constant-on circuit is grounded, the second passable circuit is turned on, and the voltage-lowering circuit operates to lower the voltage at the control terminal of the power output circuit, causing the power output circuit to transition from a sudden voltage state to a stable voltage output state.

[0074] The heavy load current of the first current source I1 is 10 times or more than the light load current of the first current source I1 . The light load current of the first current source I1 is the minimum load current generated by the first current source I1 .

[0075] refer to Figure 2 , Figure 2 A circuit diagram of a linear regulator without external capacitors provided in the first aspect of the present application. In one possible design of the present application, the first regulation circuit includes: a first transistor Q1, a second transistor Q2, a second current source I2, a first capacitor C1, and a first resistor R1.

[0076] The first end of the first transistor Q1 is electrically connected to the output end A2 of the linear regulator, the second end of the first transistor Q1 is electrically connected to the first end of the first capacitor C1, and the third end of the first transistor Q1 is electrically connected to the first end of the first constant-pass circuit and the first end of the second passable circuit respectively.

[0077] A first end of the second transistor Q2 is electrically connected to the output end A2 of the linear regulator, a second end of the second transistor Q2 is electrically connected to the first end of the first resistor R1, and a third end of the second transistor Q2 is electrically connected to the first end of the second current source I2; a second end of the second current source I2 is grounded; and a second end of the first capacitor C1 is grounded.

[0078] The second end of the first resistor R1 is electrically connected to the first end of the first capacitor C1.

[0079] refer to Figure 2 In one possible design of the present application, when the first regulation circuit is in the on state, the first transistor Q1 and the second transistor Q2 are turned on, and the second current source I2 generates current. The second transistor Q2 is configured to mirror the current generated by the second current source I2 to the first transistor Q1, thereby maintaining the first transistor Q1 and the second transistor Q2 in a constant on state.

[0080] The first end of the first transistor Q1 is the source of the first transistor Q1; the second end of the first transistor Q1 is the gate of the first transistor Q1; and the third end of the first transistor Q1 is the drain of the first transistor Q1. The first end of the second transistor Q2 is the source of the second transistor Q2; the second end of the second transistor Q2 is the gate of the second transistor Q2; and the third end of the second transistor Q2 is the drain of the second transistor Q2.

[0081] The first end of the first capacitor C1 is the positive terminal of the first capacitor C1, and the second end of the first capacitor C1 is the negative terminal of the first capacitor C1. The first end of the first resistor R1 is the positive potential terminal of the first resistor R1; the second end of the first resistor R1 is the negative potential terminal of the first resistor R1. The first end of the first current source I1 is the positive electrode of the first current source I1; the second end of the first current source I1 is the negative electrode of the first current source I1.

[0082] When the output voltage of the linear regulator output terminal A2 does not increase suddenly, the first transistor Q1 and the second transistor Q2 are turned on by the second current source I2. At this time, the second current source I2 generates a second current, which flows into the first constant-on circuit through the first transistor Q1.

[0083] When the output voltage connected to the output terminal A2 of the linear regulator suddenly increases, the first transistor Q1 and the second transistor Q2 are turned on based on the second current source I2. At this time, the second current source I2 generates a second current. The voltage at the first end of the first transistor Q1 and the voltage at the first end of the second transistor Q2 suddenly increase. Since the second end of the first transistor Q1 is electrically connected to the first end of the first capacitor C1, when the voltage at the first end of the first transistor Q1 changes, the voltage at the second end of the first transistor Q1 remains unchanged. The voltage difference between the first end and the second end of the first transistor Q1 increases, thereby forming a large current. The third end of the first transistor Q1 outputs the first current. After being diverted, the first current flows into the first constant-pass circuit and the second passable circuit.

[0084] In addition, the second transistor Q2 is electrically connected to the first end of the first capacitor C1 via the first resistor R1. Therefore, when the voltage at the first end of the second transistor Q2 increases, the voltage at the second end of the second transistor Q2 also increases as the voltage at the first end of the second transistor Q2 increases. Furthermore, changes in the voltage at the second end of the second transistor Q2 do not affect the voltage at the second end of the first transistor Q1.

[0085] refer to Figure 1 In one possible design, the linear regulator further includes: a second regulating circuit, a first end of the second regulating circuit is also electrically connected to the output end A2 of the linear regulator, and a second end of the second regulating circuit is electrically connected to the first end of the pull-down voltage circuit.

[0086] The second regulating circuit is configured to ground the first constant-on circuit within a first time period when the first current source I1 indicates that the output voltage suddenly increases.

[0087] The first regulating circuit is specifically configured to ground the first constant-on circuit and turn on the second passable circuit after a second time period when the first current source I1 indicates that the output voltage suddenly increases.

[0088] The second regulation circuit in the linear regulator of the present application is electrically connected between the linear regulator's output terminal A2 and the first terminal of the voltage-pulling circuit. Furthermore, when the output voltage at the linear regulator's output terminal A2 suddenly increases, the voltage at the second terminal of the second regulation circuit increases accordingly, generating a large current in the voltage-pulling circuit, thereby causing the voltage-pulling circuit to lower the voltage at the control terminal of the power output circuit.

[0089] Furthermore, the first regulating circuit and the second regulating circuit may be used in combination in a linear regulator.

[0090] In addition, the response speed of the second regulating circuit is faster than that of the first regulating circuit. When the output voltage at the output terminal A2 of the linear regulator suddenly increases, the second regulating circuit can reduce the amplitude of the output voltage at the output terminal A2 of the linear regulator during the response of the first regulating circuit.

[0091] Furthermore, when the output voltage at output terminal A2 of the linear regulator suddenly increases, the first and second regulation circuits can be used independently. The specific use of the first and second regulation circuits in this case can be determined based on the specific requirements of different designs.

[0092] When the output voltage at output terminal A2 of the linear regulator suddenly increases for a first duration, the voltage at the control terminal of the power output circuit is reduced based on the second regulation circuit. In this case, the first regulation circuit responds to the sudden increase in the output voltage at output terminal A2 of the linear regulator. After the output voltage at output terminal A2 of the linear regulator suddenly increases for a second duration, the first regulation circuit generates a first current to ground the first constant-on circuit and turn on the second passable circuit.

[0093] The first duration is independent of the second duration. The second duration represents the response time of the first regulating circuit. During the first duration, the second permeable circuit can be turned off or on. When the second permeable circuit is turned on during the first duration, the magnitude of the sudden increase in the output voltage at the output terminal A2 of the linear regulator can be further effectively reduced.

[0094] In one possible design, the second regulating circuit includes: a second capacitor C2.

[0095] A first end of the second capacitor C2 is electrically connected to the output end A2 of the linear regulator, and a second end of the second capacitor C2 is electrically connected to the first end of the pull-down voltage circuit.

[0096] refer to Figure 2 In one possible design of the present application, the second regulation circuit can be a second capacitor C2. When the output voltage connected to the output terminal A2 of the linear regulator suddenly increases, the voltage at the first terminal of the second capacitor C2 increases with the increase in the output voltage connected to the output terminal A2 of the linear regulator. The voltage at the second terminal of the second capacitor C2 increases with the increase in the voltage at the first terminal of the second capacitor C2. In a short period of time, the voltage at the first terminal of the pull-down voltage circuit increases, causing a large current to be generated in the pull-down voltage circuit, thereby lowering the voltage at the control terminal of the power output circuit.

[0097] refer to Figure 2 In one possible design, the first constant-on circuit includes: a third current source I3; a first end of the third current source I3 is electrically connected to the second end of the first regulating circuit, and a second end of the third current source I3 is grounded.

[0098] In one possible design of the present application, the first constant-on circuit may be a third current source I3. The third current source I3 is constantly on and is used to consume the current output by the third terminal of the first transistor Q1. This prevents the second passable circuit from being turned on when the first transistor Q1 passes the second current.

[0099] The current of the third current source I3 is greater than the current of the second current source I2, so that when the output voltage connected to the output terminal A2 of the linear regulator does not suddenly increase, the first transistor Q1 is turned on, but the current output by the first transistor Q1 is less than the current of the third current source I3, and the second pass circuit is cut off.

[0100] refer to Figure 2 In one possible design, the second passable circuit includes: a diode D1, the anode of the diode D1 is electrically connected to the second end of the first regulating circuit, and the cathode of the diode D1 is electrically connected to the first end of the pull-down voltage circuit.

[0101] refer to Figure 2In one possible design of the present application, the second conductive circuit may be a diode D1. The anode terminal of the diode D1 is electrically connected to the third terminal of the first transistor Q1 in the first regulation circuit. When the output voltage connected to the output terminal A2 of the linear regulator suddenly increases, a large current is generated in the first transistor Q1, and the third terminal of the first transistor Q1 outputs the first current. After the first current is split, part of the current flows into the diode D1, causing the diode D1 to turn on. The diode D1 is turned off when the output voltage connected to the output terminal A2 of the linear regulator does not suddenly increase.

[0102] refer to Figure 2 In one possible design, the voltage pull-down circuit includes: a third transistor Q3, a fourth transistor Q4, and a fourth current source I4.

[0103] A first end of the third transistor Q3 is grounded, a second end of the third transistor Q3 is electrically connected to the second end of the fourth transistor Q4 , and a third end of the third transistor Q3 is electrically connected to the cathode of the diode D1 .

[0104] A first terminal of the fourth transistor Q4 is grounded, and a third terminal of the fourth transistor Q4 is electrically connected to a control terminal of the power output circuit.

[0105] A first end of the fourth current source I4 is electrically connected between the second end of the third transistor Q3 and the second end of the fourth transistor Q4 , and a second end of the fourth current source I4 is used to access the power supply voltage.

[0106] refer to Figure 2 In one possible design of the present application, when the output voltage at the output terminal A2 of the linear regulator suddenly increases, the current after the first current is diverted flows into the third transistor Q3 via the diode D1. The current in the third transistor Q3 increases. The current of the third transistor Q3 is mirrored to the fourth transistor Q4 via the fourth current source I4. The current in the fourth transistor Q4 also increases. At this time, the current output by the fourth transistor Q4 is greater than the current output by the amplifier 1. The voltage pull-down circuit lowers the voltage at the control terminal of the power output circuit, effectively reducing the magnitude of the sudden increase in the output voltage at the output terminal A2 of the linear regulator.

[0107] The current of the fourth current source I4 can be low, and it is sufficient to ensure that the third transistor Q3 and the fourth transistor Q4 remain in a constant on state. When the diode D1 in the second passable circuit is turned on, the third transistor Q3 and the fourth transistor Q4 are turned on. Therefore, the third transistor Q3 and the fourth transistor Q4 in the voltage pull-down circuit can respond quickly, thereby quickly lowering the voltage at the control terminal of the power output circuit.

[0108] The first end of the third transistor Q3 is the source of the third transistor Q3; the second end of the third transistor Q3 is the gate of the third transistor Q3; and the third end of the third transistor Q3 is the drain of the third transistor Q3. The first end of the fourth transistor Q4 is the source of the fourth transistor Q4; the second end of the fourth transistor Q4 is the gate of the fourth transistor Q4; and the third end of the fourth transistor Q4 is the drain of the fourth transistor Q4.

[0109] refer to Figure 2 In one possible design, the power output circuit includes: a fifth transistor Q5.

[0110] The third end of the fifth transistor Q5 is used to access the power supply voltage, the second end of the fifth transistor Q5 is electrically connected to the output end of the amplifier 1, and the first end of the fifth transistor Q5 is electrically connected to the output end A2 of the linear regulator and the first end of the voltage feedback circuit respectively.

[0111] The voltage feedback circuit includes a second resistor R2 and a third resistor R3.

[0112] A first end of the second resistor R2 is electrically connected to the output end A2 of the linear regulator, and a second end of the second resistor R2 is electrically connected to a first end of the third resistor R3.

[0113] A second end of the third resistor R3 is grounded.

[0114] The third terminal A3 of the voltage feedback circuit is located between the second terminal of the second resistor R2 and the first terminal of the third resistor R3.

[0115] refer to Figure 2 In one possible design of the present application, the output terminal of the amplifier 1 and the third terminal of the fourth transistor Q4 are both electrically connected to the second terminal of the fifth transistor Q5. When the output voltage connected to the output terminal A2 of the linear regulator does not suddenly increase, the current outputted by the third terminal of the fourth transistor Q4 is less than the current outputted by the output terminal of the amplifier 1. In this case, the voltage pull-down circuit does not pull down the voltage at the third terminal of the fifth transistor Q5.

[0116] When the output voltage at the linear regulator's output terminal A2 suddenly increases, the current outputted by the third terminal of the fourth transistor Q4 exceeds the current outputted by the output terminal of the amplifier 1. At this point, the voltage pull-down circuit pulls down the voltage at the third terminal of the fifth transistor Q5. The third terminal of the fifth transistor Q5 serves as the control terminal for the power output circuit. The second terminal of the voltage pull-down circuit serves as the third terminal of the fourth transistor Q4.

[0117] The third terminal A3 of the voltage feedback circuit is electrically connected to the feedback input terminal of the amplifier 1. The first terminal of the fifth transistor Q5 is the source of the fifth transistor Q5; the second terminal of the fifth transistor Q5 is the gate of the fifth transistor Q5; and the third terminal of the fifth transistor Q5 is the drain of the fifth transistor Q5.

[0118] refer to Figure 2 When the output voltage connected to the output terminal A2 of the linear voltage regulator of the present application suddenly increases, the specific operation of the linear voltage regulator of the present application is as follows.

[0119] refer to Figure 2 When the current of the first current source I1 in the linear regulator of the present application rapidly decreases from a heavy-load current to a light-load current, the bandwidth of the amplifier 1 cannot respond in time. As a result, the voltage at the source of the fifth transistor Q5 momentarily overshoots, causing the output voltage at the output terminal A2 of the linear regulator to suddenly increase.

[0120] Therefore, the voltage at the source of the first transistor Q1 suddenly increases. Since the gate of the first transistor Q1 is electrically connected to the first capacitor C1, the voltage at the gate of the first transistor Q1 does not increase based on the increase in the voltage at the source of the first transistor Q1. Therefore, the voltage difference between the gate and source of the first transistor Q1 increases, causing the on-state current of the first transistor Q1 to increase. That is, the first transistor Q1 generates a large current, and the drain of the first transistor Q1 outputs the first current.

[0121] After being split, the first current flows into the third current source I3 and the diode D1, respectively. The current flowing through the diode D1 flows into the third transistor Q3, causing the current of the third transistor Q3 to increase. Correspondingly, the current of the fourth transistor Q4 increases as the current of the third transistor Q3 increases. At this point, the current output by the fourth transistor Q4 is greater than the current output by the amplifier 1. Therefore, the fourth transistor Q4 pulls down the voltage at the gate of the fifth transistor Q5. Furthermore, the voltage at the output terminal A2 of the linear regulator decreases.

[0122] In addition, the response speed of the second capacitor C2 can be faster than the response speed of the first transistor Q1. Before the first transistor Q1 responds, the first capacitor C1 responds to ensure that the output voltage of the linear regulator does not have a large overshoot voltage.

[0123] refer to Figure 2 Furthermore, the current of the second current source I2 is mirrored to the first transistor Q1 by the second transistor Q2, which can ensure that the first transistor Q1 is in the on state, and the current of the third current source I3 is greater than the current of the second current source I2.

[0124] When the output voltage at the output terminal of the linear regulator does not overshoot, the current flowing through the first transistor Q1 is consumed by the third current source I3 and does not flow into the third transistor Q3. At this time, no large current is mirrored by the fourth transistor Q4 to pull down the gate terminal of the fifth transistor Q5. The fourth current source I4 has a small current, which can ensure that the third transistor Q3 and the fourth transistor Q4 are always in the on state. The diode D1 prevents the current of the fourth current source I4 from being consumed by the third current source I3.

[0125] From the saturation current formula (1), we can see that the saturation current of the transistor I ds and When the current of the first current source I1 changes dynamically, the output voltage of the linear regulator output terminal A2 is slightly higher than the output voltage of the linear regulator output terminal A2 after stabilization. Where W is the width of the transistor, L is the length of the transistor, V gs is the gate voltage of the transistor, V th is the threshold voltage of the transistor, and μ is the electron mobility in the transistor.

[0126] When the output voltage at the linear regulator's output terminal A2 is slightly higher than the stabilized output voltage at the linear regulator's output terminal A2, the on-state current of the first transistor Q1 increases exponentially. When the current in the first transistor Q1 exceeds the maximum current allowed by the third current source I3, a portion of the current from the first transistor Q1 flows through the diode D1 into the third transistor Q3. The current in the third transistor Q3 is mirrored by the fourth transistor Q4. The current output by the fourth transistor Q4 then discharges charge to the gate of the fifth transistor Q5, thereby stabilizing the output voltage at the linear regulator's output terminal A2. This prevents significant overshoot glitches in the output voltage at the linear regulator's output terminal A2, protecting the power supply stability and performance of the downstream circuits.

[0127] In the linear regulator of the present application, the first regulating circuit, the first constant-on circuit, the second enable circuit, the second regulating circuit, and the voltage-lowering circuit constitute an overshoot protection circuit. Based on the overshoot protection circuit, the linear regulator of the present application effectively reduces the voltage at the output terminal A2 of the linear regulator, thereby preventing a large overshoot spike voltage from being generated in the linear regulator.

[0128] refer to Figure 3 , Figure 3 The output voltage change curve comparison diagram of the linear regulator of the present application and the first linear regulator when the current of the first current source I1 changes. The first linear regulator is a linear regulator without an overshoot protection circuit and an external capacitor.

[0129] Figure 3In the figure, the dashed line corresponding to V1 represents the sudden increase curve of the output voltage of the first linear regulator; the solid line corresponding to V2 represents the sudden increase curve of the output voltage of the linear regulator provided by the present application. The dashed line corresponding to I represents the current variation curve of the first current source I1 in the linear regulator without external capacitors provided by the present application. The current variation of the current source electrically connected between the output terminal of the first linear regulator and the ground terminal in the first linear regulator is the same as the current variation of the first current source I1 in the linear regulator provided by the present application.

[0130] like Figure 3 As shown, when the current of the first current source I1 in the linear regulator suddenly changes from a heavy-load current to a light-load current, the bandwidth of the amplifier 1 in the linear regulator cannot respond in time. This causes the output voltage of the linear regulator to suddenly increase. The output voltage of the linear regulator according to the present application can effectively reduce the magnitude of the sudden increase in the output voltage at the output terminal A2 of the linear regulator. This ensures that the output voltage of the linear regulator output terminal A2 is more stable, preventing large overshoot spikes.

[0131] In addition, the amplitude of the output voltage surge at the output terminal A2 of the linear regulator can be adjusted based on adjusting the sizes of the first resistor R1 and the second capacitor C2, so that the amplitude of the output voltage surge at the output terminal A2 of the linear regulator is within the target amplitude range.

[0132] In a second aspect, the present application provides a chip comprising any of the linear regulators described above.

[0133] In a third aspect, the present application provides an electronic device comprising any of the linear regulators described above.

[0134] The beneficial effects of the chip provided in the above-mentioned second aspect and each possible design of the second aspect, and the electronic device provided in the above-mentioned third aspect and each possible design of the third aspect, can be referred to the beneficial effects brought about by the above-mentioned first aspect and each possible design of the first aspect, and will not be repeated here.

Claims

1. A linear voltage regulator without external capacitors, characterized in that: The linear voltage regulator includes: an amplifier, a first regulating circuit, a first constant-on circuit, a second passable circuit, a voltage-lowering circuit, a power output circuit, a voltage feedback circuit, and a first current source; The positive input terminal of the amplifier is used to receive a reference voltage, the negative input terminal of the amplifier is used to receive a feedback voltage, the output terminal of the amplifier is electrically connected to the control terminal of the power output circuit, the first terminal of the power output circuit is used to receive a power supply voltage, the second terminal of the power output circuit is electrically connected to the output terminal of the linear regulator and the first terminal of the voltage feedback circuit respectively, the output terminal of the linear regulator is used to receive an output voltage, the second terminal of the voltage feedback circuit is grounded, and the third terminal of the voltage feedback circuit is used to output the feedback voltage, the first terminal of the first current source is also electrically connected to the output terminal of the linear regulator, and the second terminal of the first current source is grounded; The first end of the first regulating circuit is also electrically connected to the output end of the linear regulator, the second end of the first regulating circuit is electrically connected to the first end of the first constant-on circuit and the first end of the second passable circuit respectively, the second end of the first constant-on circuit is grounded, the second end of the second passable circuit is electrically connected to the first end of the pull-down voltage circuit, and the second end of the pull-down voltage circuit is also electrically connected to the control end of the power output circuit; The first regulating circuit is configured to ground the first constant-on circuit and cut off the second passable circuit when the first current source does not indicate that the output voltage has suddenly increased; The voltage-lowering circuit is configured to stop working after the second passable circuit is cut off; wherein, when the voltage-lowering circuit stops working, the working state of the power output circuit remains unchanged, so that the output voltage is output; The first regulating circuit is further configured to ground the first constant-on circuit and turn on the second passable circuit when the first current source indicates that the output voltage has suddenly increased; The voltage-lowering circuit is further configured to operate after the second passable circuit is turned on; wherein, after the voltage-lowering circuit operates, the operating state of the power output circuit changes, so that the output voltage is reduced.

2. The linear regulator according to claim 1, wherein: The first regulating circuit includes: a first transistor, a second transistor, a second current source, a first capacitor and a first resistor; A first end of the first transistor is electrically connected to the output end of the linear regulator, a second end of the first transistor is electrically connected to the first end of the first capacitor, and a third end of the first transistor is electrically connected to the first end of the first constant-on circuit and the first end of the second passable circuit respectively; A first terminal of the second transistor is electrically connected to the output terminal of the linear regulator, a second terminal of the second transistor is electrically connected to the first terminal of the first resistor, and a third terminal of the second transistor is electrically connected to the first terminal of the second current source; a second terminal of the second current source is grounded; and a second terminal of the first capacitor is grounded; The second end of the first resistor is electrically connected to the first end of the first capacitor.

3. The linear regulator according to claim 1, wherein: The linear regulator further includes: a second regulating circuit, a first end of the second regulating circuit also electrically connected to the output end of the linear regulator, and a second end of the second regulating circuit electrically connected to the first end of the pull-down voltage circuit; the second regulating circuit is configured to ground the first constant-on circuit within a first duration when the first current source indicates that the output voltage has suddenly increased; The first regulating circuit is specifically configured to ground the first constant-on circuit and turn on the second passable circuit after a second time period when the first current source indicates that the output voltage has suddenly increased.

4. The linear regulator according to claim 3, wherein: The second regulating circuit includes: a second capacitor; A first end of the second capacitor is electrically connected to the output end of the linear regulator, and a second end of the second capacitor is electrically connected to the first end of the voltage pull-down circuit.

5. The linear regulator according to claim 1, wherein: The first constant-on circuit includes: a third current source; a first end of the third current source is electrically connected to the second end of the first regulating circuit, and a second end of the third current source is grounded.

6. The linear regulator according to claim 1, wherein: The second passable circuit includes: a diode, wherein the anode of the diode is electrically connected to the second end of the first regulating circuit, and the cathode of the diode is electrically connected to the first end of the voltage-lowering circuit.

7. The linear regulator according to claim 6, wherein: The pull-down voltage circuit includes: a third transistor, a fourth transistor and a fourth current source; A first terminal of the third transistor is grounded, a second terminal of the third transistor is electrically connected to the second terminal of the fourth transistor, and a third terminal of the third transistor is electrically connected to the cathode of the diode; A first terminal of the fourth transistor is grounded, and a third terminal of the fourth transistor is electrically connected to a control terminal of the power output circuit; The first end of the fourth current source is electrically connected between the second end of the third transistor and the second end of the fourth transistor, and the second end of the fourth current source is used to access the power supply voltage.

8. The linear regulator according to claim 1, wherein: The power output circuit includes: a fifth transistor; The first end of the fifth transistor is used to access the power supply voltage, the second end of the fifth transistor is electrically connected to the output end of the amplifier, and the third end of the fifth transistor is electrically connected to the output end of the linear regulator and the first end of the voltage feedback circuit respectively; The voltage feedback circuit includes: a second resistor and a third resistor; A first end of the second resistor is electrically connected to the output end of the linear regulator, and a second end of the second resistor is electrically connected to the first end of the third resistor; The second end of the third resistor is grounded; The third terminal of the voltage feedback circuit is located between the second terminal of the second resistor and the first terminal of the third resistor.

9. A chip, characterized in that: The linear regulator comprises the linear regulator according to any one of claims 1 to 8.

10. An electronic device, characterized in that: The linear regulator comprises the linear regulator according to any one of claims 1 to 8.

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